首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 343 毫秒
1.
合欢吉丁虫(Agrilussp.)是合欢树的主要蛀干害虫,引起树干流胶导致合欢树整株死亡。该虫一年发生一代,以不同龄期的幼虫在被害枝干内越冬,成虫羽化盛期为5月上、中旬,幼虫一直为害至10月份开始越冬,合欢吉丁虫幼虫期有3种寄生性天敌。  相似文献   

2.
Cotton crop Ethiopia is a high-value crop and the strategy for pest control is insecticide-dependent with no consideration of beneficial insects. We carried out a study in 2013 and 2014 to determine the effectiveness of a food spray product developed with local ingredients from Benin (BFP), a food spray product developed from Ethiopian ingredients (EFP), and mixtures of the individual food spray products with and without neem extracts. Applications of BFP and of EFP alone attracted and retained beneficial insects and significantly reduced the number of pests, and increased cotton yields and profitability. The net margins of 18,418 and 18,642 Ethiopian birr (ETB)/ha were achieved from the plots treated with BFP and EFP, respectively, and 13,000 ETB (US$1 = 19 ETB) was achieved from the unsprayed plots. Addition of neem extract to the food spray products decreased the number of beneficial insects attracted to the food spray plots. In conclusion, food sprays can be used as part of integrated pest management (IPM) for managing cotton pests and can result in significant increases in crop yields and profitability.  相似文献   

3.
The Annona seed borer, Bephratelloides pomorum (Hymenoptera: Eurytomidae), is the most important insect pest of soursop, Annona muricata L. The female lays eggs directly into the most recently formed seeds of developing fruit where the larvae remain feeding until pupation. When fully developed, the young wasps make a channel to emerge from the fruit, ready to copulate. Males are attracted to females and display a peculiar behaviour which consists of three steps: antennation, lateral bouncing and wing vibrations. Experiments carried out in semi-field and laboratory conditions showed that males also behave similarly in the presence of filter paper impregnated with a hexane extract of the female's body, suggesting that female B. pomorum produce an attractant which enables males to find them. The hexane extracts of females, analysed by GC-MS, were shown to consist mainly of a mixture of straight- and branched-chain hydrocarbons and esters. © 1998 Society of Chemical Industry  相似文献   

4.
This study aimed to elucidate the population dynamics of Rhizoctonia, Oculimacula, and Microdochium species, causing the stem base disease complex of sharp eyespot, eyespot, and brown foot rot in cereals. Pathogen DNA in soil, roots, and stem fractions, and disease expression were quantified in 102 English wheat fields in two seasons. Weather data for each site was collected to determine patterns that correlate with assessed diseases. Oculimacula spp. (66%) and R. solani AG 2-1 (63%) were most frequently detected in soil, followed by R. cerealis (54%) and Microdochium spp. (33%). Oculimacula spp. (89%) and R. cerealis (56%) predominated on roots and soil but were not associated with root rot symptoms, suggesting that these species used soil and roots for survival and as inoculum source. M. nivale was more frequently detected than M. majus on stems up to GS 21–30 and co-occurred on plant samples with O. acuformis. O. yallundae had higher DNA concentration than O. acuformis at the lower 5 cm basal region at GS 37–45. R. cerealis predominated in the upper 15 cm above the base beyond stem extension. Brown foot rot by Microdochium spp. was favoured by cool and wet autumns/winters and dominated in English wheat. Eyespot and sharp eyespot disease index by Oculimacula spp. and R. cerealis, respectively, correlated with wet/humid springs and summers. Results suggested that stem base pathogens generally coexisted; however, their abundance in time and space was influenced by favourable weather patterns and host development, with niche differentiation after stem extension.  相似文献   

5.
毕氏海莲子和盐角草幼苗对PEG 6000模拟干旱的生理响应   总被引:1,自引:1,他引:0  
以不同浓度PEG 6000模拟干旱处理,研究了盐生植物毕氏海蓬子和盐角草幼苗的抗旱性。结果表明:随着PEG 6000浓度的上升,毕氏海蓬子和盐角草体内主要抗氧化酶SOD,POD,CAT活性总体呈先升后降,盐角草SOD活性呈上升趋势。毕氏海蓬子产生速率高于盐角草,且随着干旱的加剧呈上升趋势。盐角草MDA含量基本趋于稳定,毕氏海蓬子MDA的含量虽低于盐角草,但随着干旱的加剧呈上升趋势。毕氏海蓬子的脯氨酸含量随干旱程度的加剧先上升再下降,盐角草的脯氨酸含量一直上升,两者可溶性蛋白含量变化不大。叶绿素含量总体随干旱递增,叶绿素a/b随干旱程度加剧先略有增加然后大幅度下降。总体来看,盐生植物抗氧化酶活性是水分胁迫的敏感指标,而盐角草耐旱能力比毕氏海蓬子要强。  相似文献   

6.
干旱胁迫对藜叶片干旱诱导蛋白的影响   总被引:1,自引:0,他引:1  
采用SDS-PA GE(十二烷基硫酸钠-聚丙烯酰胺)凝胶电泳法进行蛋白质的分离,研究干旱胁迫对藜叶片干旱诱导蛋白的影响.结果表明:干旱胁迫10 d,中度干旱藜的叶片110.3 KD和103.9 KD及24.8 KD,22.7KD,21.0 KD蛋白谱带明显加强,重度干旱胁迫下22.7 KD,21.0 KD蛋白谱带增强,但弱于中度干旱胁迫;干旱胁迫15 d,中度干旱胁迫下蛋白谱带与第10 d中度干旱胁迫下的蛋白谱带相比,26.4 KD和19.2 KD蛋白谱带增强.这说明干旱诱导了藜一些适应水分胁迫相关基因的表达,或使一些基因的表达量增强,导致一些新蛋白质的出现或某些蛋白质量的增加而增强其对干旱胁迫的抵抗能力.  相似文献   

7.
外来刺萼龙葵与本地龙葵的比较   总被引:1,自引:0,他引:1  
外来入侵植物刺萼龙葵与我国本地龙葵在分类学上同属茄科(Solanaceae)茄属(Solanum),但在形态特征、发生分布、生物学特性、化学成分及生物活性、重要性及利用价值方面却存在差异。本文主要从以上几个方面对刺萼龙葵和龙葵进行论述比较,以期为这2种茄属植物的深入研究提供参考。  相似文献   

8.
张燕 《植物保护》2007,33(4):86-89
在贵阳,栽种在公园、校园、住宅小区等地的女贞普遍受到女贞瘤瘿螨(Aceria sp.)的为害,标本经有关专家鉴定为一新种。本文对此种瘿螨的形态鉴别特征、危害性和周年发生特点进行了初步研究。  相似文献   

9.
新疆棘豆属物种多样性分析   总被引:1,自引:1,他引:0  
新疆棘豆属植物有98种2变种,占中国棘豆属总种数的67.1%,其中新疆特有种7种,中国新疆仅分布种58种,特有种与新疆仅分布种共占65%,所占比例较高.棘豆属在新疆的11个植被区域中均有分布,最丰富的地区为准噶尔和天山地区,尤以天山山系种类最多,它们是棘豆属现代分布与起源分化中心之一;绝大部分种类(约99%)集中分布在海拔1 001~5 000 m的山区,尤其在1 001~4 000 m最丰富,在2 001~3 000 m分布最多;植物生活型以地面芽植物为主,高达96%,地上芽植物仅占4%.植物区系与其邻近的青海省和西藏关系最为密切,相似性系数分别为28.8%和28.6%,与内蒙古和甘肃联系相对较弱;与邻国哈萨克斯坦关系最密切,相似性系数高达65.2%,其次是西西伯利亚和吉尔吉斯斯坦,相似性系数分别为41.8%和41.0%,与蒙古、塔吉克斯坦和巴基斯坦的相似性系数较低,分别为29.2%,22.8%和11.6%,联系相对较弱.  相似文献   

10.
黄瓜绿粉病病原鉴定及其发生规律研究   总被引:4,自引:0,他引:4  
黄瓜绿粉病是温棚蔬菜上一种新病害,由绿藻门集球藻(Palmellococcus sp.)引起。藻孢卵圆形、长椭圆形、淡绿色、单胞、大小3.39~12.38μm×1.06~10.82μm,表面有山脊状隆起,是一种依附于体表的气生性自养生物。该病害多在1~3月份发生,与湿度密切相关。每日温棚中RH不低于80%,RH100%在12h以上,藻孢生长旺盛;当中午有1h以上RH低于70%时,藻孢的发育受到抑制。凡能增大温棚湿度的栽培措施如灌水、密植等因素均能加重发病。黄瓜品种抗病性无明显差异。  相似文献   

11.
伊犁谷地盐渍土的类型和特性   总被引:1,自引:0,他引:1  
伊犁谷地是新疆盐渍土分布面积最小的地区,据新疆荒地考察队资料:该区有盐渍化土壤2.76万公顷,盐渍土1.79万公顷,仅占谷地平原区面积的2.28%和1.48%;而塔里木盆地北部和南部的盐渍化土壤、盐渍土分别占该平原区面积的11.39%、30.81%和38.00%、35.12%。 1.盐渍土的形成及主要特点伊犁谷地位处我国境内天山西段,东南北三面环山,地势东高西低,东窄西宽,形似楔形,使西来湿润气流长驱直入东部谷地,而来自准噶尔盆地的干冷气流和塔里木盆地的干热  相似文献   

12.
用 Leslie矩阵对内蒙古与宁夏的西鄂尔多斯残遗分布的特有植物 -四合木(Tetraena mongolica)种群动态在张慧荣等人研究工作的基础上再作探讨。从调查数据中提取信息 ,构造新的 Leslie矩阵 ,对四合木种群年龄分级提出合理的划分。可以认为四合木种群动态有微小波动的特点。各龄级个体数的变化趋势不同 ,但种群动态在总体上呈衰退趋势。  相似文献   

13.
Creontiades spp. (Hemiptera: Miridae) are sucking pests that attack buds, flowers and young pods in mungbeans, Vigna radiata (L.), causing these structures subsequently to abort. If left uncontrolled, mirids can cause 25-50% yield loss. Traditional industry practice has involved prophylactic applications of dimethoate to control mirids at budding and again a week later. The present trial was initiated to highlight the dangers of such a practice, in particular the risk of a subsequent Helicoverpa spp. lepidopteran pest outbreak. A single application of dimethoate halved the population of important natural enemies of Helicoverpa spp., and caused an above-threshold outbreak of Helicoverpa spp. within 11 days. This shows that even a moderate (e.g. 50%) reduction in natural enemies may be sufficient to increase Helicoverpa spp. populations in mungbeans. As a result, prophylactic sprays should not be used for the control of mirids in mungbeans, and dimethoate should be applied only when mirids are above the economic threshold. Indoxacarb was also tested to establish its effect on Helicoverpa spp., mirids and natural enemies. Indoxacarb showed potential for Helicoverpa spp. control and suppression of mirids and had little impact on natural enemies.  相似文献   

14.
采用回流提取、萃取等方法,以菜青虫5龄幼虫为试虫,经生物活性测定表明,水蓼95%乙醇粗提物的不同溶剂萃取物对菜青虫具有很强的拒食活性和一定的触杀作用。其中,乙醚萃取物的拒食活性和触杀作用最强。  相似文献   

15.
沙冬青生物碱成分研究   总被引:13,自引:4,他引:13  
沙冬青叶干燥粉碎后用甲醇、石油醚、氯仿提取,并采用柱层析和薄层层析等方法分离出三种生物碱,经质谱和核磁共振波谱仪鉴定为羽扇豆碱,斯帕亭和a-异斯帕亭生物碱。  相似文献   

16.
我国有16种郁金香,而新疆就占12种,我们的实验表明六种郁金香:毛蕊郁金香、准噶尔郁金香、阿勒泰郁金香、垂蕾郁金香、伊犁郁金香、异瓣郁金香含有秋水仙碱,而迟花郁金香没有秋水仙碱,上面七种郁金香都含有另外生物碱1-2种。  相似文献   

17.
本文首次报道了新疆藓类植物的一个新记录科-棉藓科Plagoitheciaceae,含-属-种,光泽棉Plagiothecium Laetum B.S.G.。文中还简要评述了棉藓科的分类历史。  相似文献   

18.
Wolfberry (Lycium barbarum) ranks in the top 10 best-selling medicinal plants in China and it has been used for centuries as a medicine and a food supplement. It is suggested to have benefits on human health due to the rich content of polysaccharides, carotenoids, flavonoids, and alkaloids contained in its fruits, leaves, and root bark. Recently, severe root rot diseases have been causing plant losses in major growing areas. Here, we report fungi causing root rot disease in Chinese wolfberry plants. The analysis of nucleotide sequences of the internal transcribed spacer (ITS) region revealed a total of 92 isolates isolated from both soil and plant material samples. Fusarium spp. were the most abundant (58%), followed by Penicillium spp. (9%), and Alternaria spp. (5%). Fusarium spp. included F. oxysporum (36%), F. solani (30%), F. chlamydosporum (9%), F. nematophilum (9%), and F. tricinctum (8%). Sequences from the translation elongation factor 1-α gene (TEF-1α) were used to confirm the identity of Fusarium spp. and showed the predominance of F. oxysporum and F. solani. To confirm the pathogenicity of isolates, four isolates belonging to Fusarium spp. and one isolate belonging to Alternaria spp., isolated from wolfberry root tissues with root rot symptoms, were tested in outdoor and laboratory conditions. Results revealed that the five tested isolates were pathogenic with varying degrees of aggressiveness and ability to induce symptoms of root rot in wolfberry seedlings. The five isolates were recovered from inoculated seedlings, completing Koch's postulates. This is the first report on causative agents of root rot in Chinese wolfberry.  相似文献   

19.
刺槐和油松根系密度分布特征研究   总被引:9,自引:3,他引:9  
通过分层挖掘法,对20龄刺槐、油松林根系密度的空间分布进行了研究.结果表明:油松主根和副主根粗壮发达,水平根系形成构架根;刺槐水平根极为发达,无明显主根.刺槐和油松根系重量、长度和体积密度的垂直分布趋势基本相同,随土层深度增加而降低.0~60 cm土层的根长和根重密度占总根量密度的70%以上,粗根(直径>3 mm)在上层所占比例比下层略大,细根(直径<1 mm)和较细根(直径1~3 mm)在各土层分布较为接近,总根量中粗根占较大比重.刺槐和油松林下土壤干密度随深度加深而增大,油松林下土壤含水量高于刺槐林,土壤干密度低于刺槐林.与刺槐林地相比,油松林地的土壤物理性质得到了明显改善,增强了土壤的抗旱、保墒能力.  相似文献   

20.
日光温室茄茎腐病病原鉴定   总被引:2,自引:0,他引:2  
1998~2000年连续 3年在甘肃省主要茄子栽培区大量采集茄子茎腐病病株和病土 ,经分离和致病性测定 ,表明引起当地茄茎腐病的主要病原为镰刀菌和疫霉菌。根据病原形态特征、培养性状以及致病性测定 ,确定其为尖镰孢菌 (Fusarium oxysporum)、黄色镰孢菌 (Fusarium culmorum)和寄生疫霉 (Phytophthora nicotianae)。两种镰刀菌生长发育最适温度均为20~30℃ ,最适pH为7.0;在光照条件下菌丝生长缓慢。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号